Background: Despite the worldwide trend toward more time being spent at work by employed people, few studies have examined the independent influences of work-based vs. home-based social networks on employees' health. We examined the association between work-based social networks and health status by controlling for home-based social networks in a cross-sectional study.
Methods: By employing a two-stage stratified random sampling procedure, 1105 employees were identified from 46 companies in Okayama, Japan, in 2007. Work-based social networks were assessed by asking the number of co-workers whom they consult with ease on personal issues. The outcome was self-rated health; adjusted odds ratio (OR) for poor health compared employees with no network with those who have larger networks.
Results: Although a clear (and inverse) dose-response relationship was found between the size of work-based social networks and poor health (OR: 1.53, 95% confidence interval: 1.03 to 2.27, comparing those with the lowest vs. highest level of social network), the association was attenuated to statistical non-significance after we controlled for the size of home-based social networks. In further analyses stratified on age-groups, among older workers (≥ 50 years), work-based social networks were apparently associated with better health status, whereas home-based networks were not. The reverse was true among middle-aged workers (30 to 49 years). No associations were found among younger workers (< 30 years).
Conclusions: The present study suggests a differential association of alternative sources of social support on health according to age-groups. We hypothesise that these patterns reflect generational differences in workers' commitment to their workplace.